The invention relates to a two-roll machine for the pressure treatment of granular material, in particular a roller press for material bed comminution or compaction or briquetting, having two rolls which are rotatably mounted in bearing housings, driven in opposite directions and separated from each other by a roll gap, one of which is formed as a loose roll whose bearing housings are supported on machine frame side parts by hydraulic cylinders applying the roll pressing force, while the bearing housings of the fixed roll are supported on frame end pieces, and all the bearing housings being mounted with their undersides and upper sides on sliding tracks of lower-flange and upper-flange machine brackets.
During roller grinding for performing what is known as material bed comminution, the individual pieces or particles of the ground material drawn into the roll gap by friction, such as cement raw material, cement clinker, ores or the like, are pressed and mutually comminuted in a material bed, that is to say in a material fill pressed together between the two roll surfaces with the application of a high pressure, mention also being made of a roller press instead of a roll mill. In previously known roller presses, see for example the brochure “Rollenpressen” [Roller presses] no. 2-300 d from KHD Humboldt Wedag AG dated September 1994, page 2, one of the two rolls is constructed as a fixed roll, which is supported via its bearing housings against end pieces of the machine frame, while the other roll, as a loose roll, is supported via its bearing housings on hydraulic cylinders, with which the roll pressing force is applied. In this case, the hydraulic cylinders in turn have to be supported on solid side parts of the machine frame, which forms an intrinsically closed force system, that is to say the radial roll pressing forces or grinding forces occurring during the operation of the roller press have to be absorbed by the machine frame.
There is a need on the part of the operators of such roller presses to be able to remove the rolls in the most simple and rapid way possible and re-install them again, for reasons of the repair of worn rolls, etc., for example, for which purpose the machine frame has to be broken down in order to make the rolls accessible in order to change them.
In order to facilitate the roll change in roller presses, it is known, for example brochure “Hochdruckzerkleinerung mit Walzenpressen” [High-pressure comminution with roll presses] from Köppem GmbH & Co. KG dated 7/87, page 6, to construct the press frames as folding frames, by side parts of the machine frame being attached to the ends of the lower flange and upper flange machine brackets via pin hinges. All the pin hinge axes lie parallel to the roll axes, so that the pin hinges are under the full loading of the high roll pressing forces. Therefore, loosening the upper locking pin hinges and actuating the lower pin hinge axes, and folding out the machine frame parts on the end in a horizontal plane can present difficulties before the rolls can then be pulled out onto the folded-out frame parts. In addition, the two rolls cannot be removed towards one side of the roll press.